Liquid filtering apparatus



Filed Dec. 2, 1929 2 Sheets-Sheet 1 June 21, 1932. N. E. NlLssoN LIQUID FILTERING APPARATUS Filed Dec. 2, 1929 2 Sheets-Sheet 2 Patented June 21, 1932 PATENT OFFICE NILS ENOK NILSSON, 0F ASPABRUK, SWEDEN a LIQUID FILTERING APPARATUS Application lred December 2, 1929, Serial No. 411,111, and in Sweden December 4, 1928.

An embodiment of a ltering apparatus according to the inventionvis illustrated in the accompanying drawings. Figure 1 shows the iilter in vertical section, and an arrangement with two filters for continuous operation, is shown in Figure 2 in plan and in Figure 3 in side view.

The filter cloths 1 and 2 are deposited in an airtight sheet metal receptacle having an intake 3 for the liquid to be cleaned from deposited particles, land an outlet 4 `for the cleaned liquid'. The separated particles are taken out through the outlet 5. In order that the filter cloths shallnot be covered with too thick a layer of particles, the filter cloth 2 obtains by means ofV a cam 6 a slow motion opposite to the direction of flow ofthe liquid, until the block 7 (Figure 1) passes the end 8 lof said cam, at which time a spring 9 rapidly moves the filter cloth 2 in the same direction as the direction of motion of the liquid. Preferably one cam 6 is located at each side of the frame 10 of the lilter cloth, the cams being mounted on a shaft 11 running through both sides of the sheet metal receptacle and journalled in said sides in suitable bearings. On the one end of the shaft 11 there islocated a sprocket 12, over which runs a chain 13 suitably driven to effect driving of the cams 6.

By the motion of the filter cloth 2 the liquid obtains a to-and-fro-motion which detaches the particles pressed against the filter cloth 2 so that they descend toward the outlet 5. The motion of the liquid is imparted to the filter cloth 1 and prevents excessive accumulation upon the latter. In order `that these particles shall descend toward the outlet 5, there are impellers 14, which at a suitable dis- Z tance from the cloth l move upwardly.

These impellers 14 are carried by a chain 16, said chain running over sprockets 17 on shafts 18, which pass through the sides of the sheet metal receptacle and are journalled in said sides by means of suitable bearings. On one of these shafts 18 there is located outside the sheet met-al receptacle a sprocket 19, over which runs a chain 20, which gives the motion to the impellers 14 from a suitable driving source. The impellers 14 are pivoted on the chain 16 in such a way, that passing upwards vkept'c'losed.

they remain hanging, but passing downwardly they Vfall out at a suitable angle to the filter cloth. As the liquid passes through the filter cloth 1 the thicker particles are separated, and when passing the filter cloth 2 those not separated by the lter cloth 1 ar-e removed.

For the purpose of drawing ofi the separated particles through piping from the outlet 5 there are located two valves 22 and 23 in the pipe 21. For the purpose of drawing off, the valve 22 is opened, whereas the valve 23 is kept closed, the intermediate space 24 being then filled; then the valve 22 is closed and the valve 23 opened, the space 24 being thus emptied. When the layer on the filter cloth 1 has become so dense that further fila trationY is substantially prevented, the liquid passes under said filter cloth 1 and the liquidcarried particles soon clog the filter cloth 2, so that a pressure increase arises in the receptacle thus showing the need of cleaning. For the purposes of cleaning the filter cloth 2 there-is located above the same a sprayer 25 for warm water, steam, gas or air, which is supplied by means of a pipe 26. lFor the purpose of cleaning the cloth 1 there is located above the same a removable manhole and cover 27 which makes it possible for the lter cloth 1 to be taken out. v

In Figure 2, two filtersy such as shown in Figure l are connecte-d for continuous operation. -The liquid to be cleaned fiows through they pipe a passes through the valve b, and passes the filter al when the valve c is From there the liquid, when the valveg is open and the valve fisclosed passes, through 'the pipe b, and the filter is'thereby maintained filled with the liquid.

- When the filter cloths 1 and 2 of the filter Z have become so dense that they need be cleaned, the liquid is taken through the filter e by opening the valves, which have been closed and closing the valves which have `been open.

Then the filter d is emptied of liquid by opening the valve f, the liquid flowing away through thepipe 7c. The liquidv having flowed awayon a level with the pipe 7c the valve f is closed and the remainder in the receptacle which consists of separated parpellers le. After cleaning, the filter is emptied, all the contents being drawn out through the pipe 5. many times as necessary in order to get the l filter cloths l and 2 entirely clean. Filter c may be cleaned in thesame way .when required, lter al being then thrown into use.

l claim: l Y

l. A filter coinprisinoa liquid receptacle having a. liquid inlet in one vertical side and a liquid outlet in its opposed side, a substantially vertical filtering screen in said receptacle between said inlet and outlet and in a plane transverse to the direction of liquid flow from said inlet to said outlet, means mounting said screen for movement toward and from said inlet and outlet and holding it against other movements, means for repeatedly moving said screen toward said inlet and for releasingit after each of such movements, and means for rapidly moving vthe screen again toward said outlet after each release of said screen, whereby the scieen is washed of particles caught thereby.

2. A filter comprising a liquid receptacle havin a liquid inlet in one vertical side and a liquid outlet in its opposed side, a substantially vertical filtering screen in said receptacle etween said inlet and outlet, means mounting said screen for movement toward and from said inlet and outlet and holding it against other movements,l a fixed substantially vertical filtering screen mounted in said receptacle at the side of said movable screen toward said liquid inlet, both of said screens being disposed in planes transverse to the direction of liquid fiow from said inlet to said outlet, and means for repeatedly moving said movable screen toward and from said fixed screen, whereby said movable screen is washed of particles caught thereby and said movable screen will pulsate the liquid to also wash said fixed screen.

3. A filter comprising a liquid receptacle having a liquid inlet in one vertical side, the opposed side of said receptacle being provided with an outwardly offset portion having a bottom, said odset portion being provided with a liquid outlet, a movably mounted filterscreen disposed in a plane transverse to the direction of liquid fiow from said inlet to said outlet, said screen extending vertically from the receptacle top to the inner edge of said bottom of said offset portion, means in said offset receptacle portion for repeatedly This is repeated" as moving said screen toward said liquid inlet and releasing it after each of such movements, and means for rapidly returning said screen after each release thereof, whereby said screen is washed of particles caught thereby.

4l. A filtering apparatus comprising a liquid receptacle having a couple of' filter screens mounted in such a position between an inlet and an outlet of the receptacle that the liquid passes in a substantially horizontal direction successively through them, the screen, situated at the outlet side in relation to the other screen, being adapted to be given a pulsating motion toward and from the last mentioned, fixed screen, further having mechanically driven means for repeatedly moving said movable screen and mechanically driven means for removing separated particles from the fixed screen toward an outlet at the bottom of the receptacle.

5. A filtering apparatus comprising a liquid receptacle having a couple of filter screens mounted in such a position between an inlet and an outlet of the receptacle that the liquid passes in a substantially.. horizontal direction successively through them, the screen, situated at the outlet side in relation to the other screen, being movably mounted, said other screen being fixed, means for slowly moving the movable screen toward the fixed screen and rapidly away from said fixed screen, and mechanically driven means for removing separated particles from the fixed screen, said particle removing means consisting of an endless driven chain, movable along the inlet side of the fixed screen and provided with a plurality of iinpellers pivoted to the chain, said impellers being adapted to project toward the fixed screen when descending and to hang vertically when ascending, thereby urging sediment from the fixed screen toward the receptacle.

In witness whereof I have hereunto signed my name.

NILS ENOK NILSSON. 

